SPOTLIGHT: Mining needs a new direction – from economies of scale to smart precision and efficient mining

The mining industry has embraced artificial intelligence (AI) and data science as the latest remedy to operational optimisation, and miners are already reaping the benefits.

For instance, Vale’s AI Centre has extended tire life by 30% and reduced costs by 7% in its pelletising plants, while Anglo American’s integration of AI in mining operations has improved haul road efficiencies, resulting in a 7% increase in the Minas-Rio throughput rate. Rio Tinto’s introduction of autonomous haul trucks has led to a 15% reduction in load and haul unit costs.

Another notable use case is Codelco’s digital data center, which is powered by machine learning (ML). The technology is adding about 8,000 metric tonnes at its Chuquicamata mine, or US$80 million in annual profit, as reported by Bloomberg via a company statement.

AI and ML can typically achieve operational improvements of 10-30%, with potential enhancements, for example, in safety rates, consumable usage, utilisation and availability, ranging from 50% to 90% in specific use cases.

The return on investment (ROI) is also typically very high. However, while these tech tools are necessary and provide notable incremental improvements, they are not sufficient to overcome a persistent roadblock for miners: declining ore grades.

Escondida: a case in point

Let’s consider Escondida, one of the world’s largest copper mines. It has undergone remarkable expansions since its inception in the early 1990s. The Los Colorados concentrator began operations at a rate of 35,000 tonnes per day. 

Back then, Escondida boasted high copper content with a mining head grade ranging from 2.5% to 3%. These favourable conditions fuelled a series of expansions, with the oxide ore leaching plant taking off in 1998, now capable of producing 150,000 tonnes of copper cathode annually.

Simultaneously, the Los Colorados concentrator expanded to 120,000 tonnes per day. Subsequent expansions included the Laguna Seca mill in 2002 and the Escondida Norte pit in 2005. These expansions harnessed economies of scale to increase production and reduce costs.

However, the tale took a turn as the highest-quality resources were exhausted by the early 2000s. Escondida’s average head grade has declined from approximately 3% at the start of operations in the 1990s to around 1% today, with further declines expected to 0.5 to 0.6% over the coming decades.

This represents a fivefold reduction from first production. Escondida now stands at a juncture where substantial capital investments are needed not to expand production, but to maintain it. 

Escondida’s story serves as a microcosm of the broader industry. The days of abundant high-quality resources that facilitated production growth through capital investments are waning.

Miners will no longer be able to rely on economies of scale to boost production while reducing costs. Instead, the prevailing paradigm mandates a shift toward smart and precise mining, one that employs more sustainable and efficient practices.

Smart solutions across the mining value chain

One area of inefficiency is mineral movement. Haul trucks, while ubiquitous, suffer from low diesel engine efficiency. They also carry excessive mass, including the mass of the truck and gangue material. Less than 10% of the haulage energy is used to move the valuable mineral. 

Replacing haul trucks with more efficient conveyor systems, such as Railveyor’s remote-controlled equipment system, has the potential to revolutionise material movement. Innovative projects like Vale’s S11D achieved a 67% reduction in energy consumption, a 73% decrease in CO₂e emissions, and a 15% reduction in operating costs. 

In the domain of concentrator efficiency, significant advancements are possible in terms of low capital improvements in existing operations and new installations.

Microwave preconditioning, a technology under development by Nottingham University with a pilot plant capable of processing 150 tonnes per hour, is showing potential. This technology is reported to improve mill throughput up to 30%, yet commercial-scale plants are still in development. 

In addition to low capital options to improve existing operations, there are also inventions underway to improve the efficiency of comminution processes between 30-90%.

The use of transcritical CO2 pulverisation marks a radical departure from traditional methods. The tensile breakage technology exploits rock’s vulnerability under tension, contrasting with conventional compression techniques. 

Pioneered by Canadian startup Rockburst Technologies, this approach is in the lab-testing phase and shows promise for significantly improved energy efficiency, although it requires further development for commercial application.

Balancing economic and ecological responsibilities

The abovementioned innovations address material movement, extraction and separation inefficiencies at the subsystem level.

New, transformational innovations such as in-situ extraction address the inefficiencies holistically at the system level and have the potential to redefine the industry’s approach, moving away from the traditional focus on economies of scale towards a precision mining approach.

The move to smart and precise mining paves a better path for the industry. It suggests that efficiency and profitability can be achieved, not only through scale, but also through innovative approaches that respect and protect our environment. 

Embracing these transformative ideas and fostering collaboration across various sectors are essential for miners to navigate the future — one where economic success is balanced with ecological responsibility.

Grant Caffery is a mining technology expert with more than 30 years of experience. He’s currently the Australia director at Clareo. Previously, he was the head of innovation at BHP where he was responsible for establishing the company’s innovation portfolio and process.